Draft-gear.



T. H. SYMINGTON.

DRAFT GEAR.

APPLIGATIQN FILED APRA 4, 1912.

Patented. N 0V. 3, 1914.

' THOMAS- H. SYMINGTON, OF BALTIMORE, MARYLAND.

DRAFT-GEAR;

Specification of Letters Patent.

, Patented Nov. 3, 1914.

Appiieatmn inea April 4,1912.` serial No. 638,456.

T all whomz't may] concern.' i

\ Be it known that I, THOMAS H. SYMI'NG- TON, a citizen of the UnitedStates of America, residing at the city of Baltimore, State of Maryland,have invented certain new and useful Improvements in Draft- Gear, ofwhich thefollowingis a specification.

The draft gear of my invention comprises `a draw-bar, a yoke securedthereto and mounted between the sills, a front stop,`a rear followerextending substantially from sill to sill and notched to' receive thearms of the yoke, shock-absorbing means between the front stop and therear follower, a rear stop in the form of an abutment on each sill, thefollower engaging the abutments at points immediately adjacent the sillsduringl bufing. p

In the preferred form of my invention the draft beams-are provided withtwo sets o-f alined, elongated slots. The horizontal yoke iscorrespondingly slotted, and the drawbar is slotted in alinementwithvthe slots of the front set in the beams vand yoke. A.

key is seated in each of slots, the rear key serving as a forward stop.Any preferred forni of mounted within the yokeand serves to transmit tothe sills, by@ way of the front stop, the drawing stress applied by thedraft gear. There is an abutment secured to each ysill acting as a rearstop,'and a rear follower, in the form of an H-shaped member, is.mountedwithin the yoke, thearms of the yoke passing throughthe notches or slots-of the-H and engaging the cross bar of the H. This follower serves totransmit builing stress applied` to the gear, from the shockabsorbingmember to the sills byv way .of the rear abutment, the extremities ofthe arms of the H bearing on the shoulders adjacent the sills, so thatthere is ,practically no bendlng moment applied to the sills, the stressbeing entirely one of compression and shearing.

In the accompanying drawing I have illustrated a draft gear embodyingthe principle of my invention in its preferred form.

Figure 1 is a lan divided on the longitudinal center line of the gear,one half being a top View, the -other being a section on the line 1, 1of Figx. Fig. 2 is a central longitudinal section, certain of the partsbeing shown in elevation. Fig. 3 is a transversever-tical section ontheline 3, 3 of Fig.

' direct to the yoke.

shock-'absorbing means is H forming top member of the H, indicated by 1.Fig..4 is an elevation of the H-shaped follower. Fig. 5 shows a modifiedform of follower. l n. Between the longitudinal sills or draft ,arms 1is a horizontal yoke 2. The sills and yokeas shown, are pierced with twosets of alined, e1ongated slots, indicated by reference characters asfollows: the slots of the front setlin the sills 4, the rear slots 5,the front slots in the yoke 6, and the rear slots' in the yoke 7.Thereis a front key 8 placed in the slots of the front set, and a rear.key

9 placed in the slots -of thev rear set. The

.draw-.bar 10 is slotted at 11 to fit the front key which passestherethrough, and the` front key serves to transmit tension stress Theslots 6 extend to ,the rear so that compression stress 'is never,applied to the yoke, and the key is also adapted to bear at timesagainst the front face-of the slot in the sill to transmit eX- tremetension direct from the draw-bar to the-sill when maximum drawing stressis applied, or to vtake a continued bearing` thereagainst during drawing-to prevent pulling out of the draw-bar when failure of the gearoccurs.: Within the arms of the yoke, as seen in plan view, is anysuitable shock-absorbing member as the springs 12. For the purpose ofreceiving the compressive force of the springs vin drawing andtransmitting the vsame'tothe rear key 9, which actsvas a front stop, andalso for the purpose of applying compressive force tothe'sprin'gs'inbufiing, I have provided a front follower 13 mounted" on the rear keyand slotted to receive the same. This follower may be of-any suitable orusual type, and transmitting pressure'at the forward end of the springsmay be substituted lIor' it. Within the arms of the yoke I have alsoshown a rear follower 14. This follower eX- tends substantially fromsill' to sill and takes its bearing during buiing on shoulders 15secured to the sills, forming rear abutments. The rear follower 14 ispreferably an H- shaped member,

and bottomarms of the follower, the extremities of which bear, duringbufing, on the shoulders 15 at points adjacent' thesills. The rear army17 of the yoke bears on the central portion or connecting 17, duringdrawing, and the notches 18 between the and any means for applying seeFigjS, the legs 16 of the 'legs of the H receive the arms of the yoke,and

permit them to be suitably spac'ed from the sills and thereby avoid thecheek plates and the key bearings, etc. adjacent the slots 4 and 5.

The operation of the gear will be clearly apparent from the descriptiontaken in connection with the accompanying drawing. The gear is shown inthe lposition which it will take when subjected to no stress. Indrawing, the stress -is transmitted. from the draw-bar to the front key8, hence to the yoke, by which it is appliedA to the rear follower. Therear follower compresses the springs or friction gear and transmitsstress to the front follower which is mounted on the rear key 9, thelatter serving a's a forward abutment. It will be noted that in normalposition this key rests against the front ends of the slots 5 in thedraft beams. As drawing is continued and the gear. is compressed, the'front key moves forward toward the front ends' of the slots 4 in thedraft beam, and under extreme stress,` bothv keys bear against the frontends of their slots and the stress is applied direct to Vthe. sills. Ifany portion of the gear fails, the

front key forms a rigid connection' between the draw-bar and sills. Thisprevents pulling out of the draw-bar. In buiiing, stress is appliedfirst by the'draw-bar to the front follower`v13 which transmits itthrough the shock-absorbing gear to the rear follower 14, by which it istransmitted from the eX- tremities of the arms 16 of the H-shapedfollower to the shoulders at points closely adjacent the sills. By,applying the stress at points closely adjacent to the central webs ofthe sills, the bending moment is substantially eliminated and consequentspreading of the sills is avoided. Under extreme buffing stress the keystake a bearing against the rear ends of their slots and thus preventdestruction of the springs. l In Fig. 5 I have illustrated another formof followerfhaving slots 2O instead of notches 17 to receive the arms ofthe yoke.

Its operation will be easily understood in connection with thedescription. The edges 21 of this follower engage the rear stopimmediately adjacent the sills in buiing as do the ends of the arms ofthe H-shaped follower.

I have thus described my invention in its preferred form in order thatits nature' and. operation may be clearly understood. However, thespecific terms' herein are used in their descriptive rather than intheir limitv inv sense.

IlVhat 'I claim and desire to secure by Letters Patent is: n

In a draft gear havin two keys only, a slotted draw-bar, a drafteam-having front and rear sets of alined slots, a horizontal yoke havingcorresponding slots, one key passing through the slot in the draw-barand seated in the forward set of slots in the yoke and draft beams, thesecond or rear key passing through the rear slots in the yoke and draftbeams and serving as a forward stop, a rear stop consisting of separate,independent\ abutments, one secured to each sill and a rear `follower inthe form of an H-shaped member, the connecting arm of the H beingencircled by the yoke and the ends of the legs of the H bearing againstthe rear stop at points immediately adjacent the sills.

Signed by me at Baltimore, Maryland, this 2d day of April, 1912.

THoMAs H. s YMINGToN.

Witnesses:

A. H. WESTON, I. O. WRIGHT.

